package com.miaomiao.utils;

import org.apache.commons.codec.binary.Base64;

import javax.crypto.Cipher;
import java.security.*;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;

/**
 * RSA加密解密
 *
 * @author ruoyi
 **/
public class RsaUtils
{
    // Rsa 私钥
    public static String privateKey = "MIICeAIBADANBgkqhkiG9w0BAQEFAASCAmIwggJeAgEAAoGBALxhCyGMfzkPFgCd\n" +
            "Ep++PncKsDnUVM+9zUIeFShjBZ9wH3zGyrvtdBvsu138FIIIXWUFtSuCvaXzPqma\n" +
            "2vkfVvsqMg6UNr6Zb054HXD8vKV3mrG8zVEMdohS8SC2+x1hYbezMEC6w5pBQNri\n" +
            "War85GvlAmDrNEP7yA8QrOp/5rsrAgMBAAECgYEAmcNEiK/bsMFlnj6X0xhAeH6a\n" +
            "9bkhOSieAFf5wSuCjW/B4+GH3fmmipyjG8YFH1aglTMhfFCNaIWyIlKqZip0ncq8\n" +
            "KViNRbXfpgLbJbHRCqj+8igU7RXnO7ZFg5t3Y+6VJ4/lQUCcxgiDdCmqRGh4WF82\n" +
            "ioONDxbgb0Cd5LrrxSECQQDyodCwT0hvZmi2RXQMl5EwHlK/5zJKdyGjtw/0W6CG\n" +
            "tCAZOPdrXi9OO77kX+uypgErI200MiNpIq1UDULId+ajAkEAxsIFYPBci9h3yqmr\n" +
            "p7TsCEUotuZYIgr0keAxWt3lBHED/WgO1LjuxE44Ymddjig+/Omdl9PWh9U3xZOn\n" +
            "8T2J2QJBAN9xicB0ox6ETzZcq8zU4E5R/p7gCX5uS7p7YeQFZcXnqA/SWHi2WhZQ\n" +
            "CzJB68uv+S+DBpSk/9tYpgrb037OfMUCQQDEczDtx6UxdBuy7FEFygUhh3nejX2+\n" +
            "6CUjqfweXAPoh+vxo9BE4STeUpHYcWI/B/h58k4Zqv/38f7WAkOUZcbBAkBagzI+\n" +
            "omwPq1bWfVdX4ATZK7x/do1gM0B2y9DggaBgBGorUQzAEexa0IFAaSvA64wMZue3\n" +
            "uwDSOQFEI67V83hS";

    /**
     * 私钥解密
     *
     * @param text 待解密的文本
     * @return 解密后的文本
     */
    public static String decryptByPrivateKey(String text) throws Exception
    {
        return decryptByPrivateKey(privateKey, text);
    }

    /**
     * 公钥解密
     *
     * @param publicKeyString 公钥
     * @param text 待解密的信息
     * @return 解密后的文本
     */
    public static String decryptByPublicKey(String publicKeyString, String text) throws Exception
    {
        X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(Base64.decodeBase64(publicKeyString));
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.DECRYPT_MODE, publicKey);
        byte[] result = cipher.doFinal(Base64.decodeBase64(text));
        return new String(result);
    }

    /**
     * 私钥加密
     *
     * @param privateKeyString 私钥
     * @param text 待加密的信息
     * @return 加密后的文本
     */
    public static String encryptByPrivateKey(String privateKeyString, String text) throws Exception
    {
        PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(Base64.decodeBase64(privateKeyString));
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.ENCRYPT_MODE, privateKey);
        byte[] result = cipher.doFinal(text.getBytes());
        return Base64.encodeBase64String(result);
    }

    /**
     * 私钥解密
     *
     * @param privateKeyString 私钥
     * @param text 待解密的文本
     * @return 解密后的文本
     */
    public static String decryptByPrivateKey(String privateKeyString, String text) throws Exception
    {
        PKCS8EncodedKeySpec pkcs8EncodedKeySpec5 = new PKCS8EncodedKeySpec(Base64.decodeBase64(privateKeyString));
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec5);
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.DECRYPT_MODE, privateKey);
        byte[] result = cipher.doFinal(Base64.decodeBase64(text));
        return new String(result);
    }

    /**
     * 公钥加密
     *
     * @param publicKeyString 公钥
     * @param text 待加密的文本
     * @return 加密后的文本
     */
    public static String encryptByPublicKey(String publicKeyString, String text) throws Exception
    {
        X509EncodedKeySpec x509EncodedKeySpec2 = new X509EncodedKeySpec(Base64.decodeBase64(publicKeyString));
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec2);
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.ENCRYPT_MODE, publicKey);
        byte[] result = cipher.doFinal(text.getBytes());
        return Base64.encodeBase64String(result);
    }

    /**
     * 构建RSA密钥对
     *
     * @return 生成后的公私钥信息
     */
    public static RsaKeyPair generateKeyPair() throws NoSuchAlgorithmException
    {
        KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
        keyPairGenerator.initialize(1024);
        KeyPair keyPair = keyPairGenerator.generateKeyPair();
        RSAPublicKey rsaPublicKey = (RSAPublicKey) keyPair.getPublic();
        RSAPrivateKey rsaPrivateKey = (RSAPrivateKey) keyPair.getPrivate();
        String publicKeyString = Base64.encodeBase64String(rsaPublicKey.getEncoded());
        String privateKeyString = Base64.encodeBase64String(rsaPrivateKey.getEncoded());
        return new RsaKeyPair(publicKeyString, privateKeyString);
    }

    /**
     * RSA密钥对对象
     */
    public static class RsaKeyPair
    {
        private final String publicKey;
        private final String privateKey;

        public RsaKeyPair(String publicKey, String privateKey)
        {
            this.publicKey = publicKey;
            this.privateKey = privateKey;
        }

        public String getPublicKey()
        {
            return publicKey;
        }

        public String getPrivateKey()
        {
            return privateKey;
        }
    }
}